Method and apparatus for annealing glassware



Jan. 26 1926. 1,571,137

v. MULHOLLAND METHOD AND APPARATUS FOR ANNEALING GLASSWARE Filed March31. 1925 figg. f

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v. MULHOLLAND METHOD AND APPARATUS FR ANNELING GLASSWRE Filed March. 3l,7 Sheets sheet 3 @er Mzzl @Z iz Q0 @ghn Azfy Jan. 26 1926.

V. MULHOLLAND METHOD AND APPARATUS FOR ANNEALING GLASSWARE Filed MarchC51. 1925 '7 Sheets-Sheet 4 Wer Z? Jan. 26 1926.

V. MULHOLLAND l METHOD AND PPARATUS FOR ANNEALING GLASSWARE Filed March31. 1925 '7 Sheets-Sheet 5 Jaim.` 26 1926. 1,571,137

v. MULHOLLAND METHOD AND APPARATUS FOR ANNEALING GLASSWARE Flled March31, 192:: 7 Sheets sheet 7 Patented Jan. 26, 1926.

UNITED STATES PATENT OFFICE.

VERGIL MULHOLLAND, 0F WEST HARTFORD, CONNECTICUT. ASSIGNOB TO HART-FORD-EMPIRE COMPANY, OF HARTFORD, CONNECTICUT, .A CORPORATION OFDELAWARE.

METHOD AND APPARATUS FOR ANNEALING GLASSWABE.

Application filed March 31, 1925.

To nl? whom 'it may concern.'

Be it known that I, Venen. HULHOLLAND, a citizen of the United States,residin at vest Hartford, in the county of Hartgord and l@tate ofConnecticut, have invented certain new and useful Improvements inlllcthods' and Apparatus for Annealing rlassware. of which the followingis a specitication.

This invention relates to a method of and apparatus for annealingglassware and particularly for annealing a continuous succession ofarticles delivered from a Ware-shaping machine. More specifically, itrelates to thc annealing of glassware in a lehr of the tunnel type inwhich the ware passes in procession through a tunnel whose temperaturevaries from end to end.

Glassware, after being shaped in a mold, is ordinarily7 removedtherefrom while still very hot and is annealed by radually cooling it toatmospheric temperaure. If merely set out in the open air it will cooltoo rapidly and unevenly. lts outer surface will cool and contract morerapidly than its interior portions. thus altering the relativedimensions and locations of different portions of the piece and creatingstresses therein, which fend to disrupt it. To avoid or minimize thesestresses is the object of annealing. If not suflciently or properlyannealed, so that undue internal stresses still exist therein, thearticle breaks easily when used or handled, and may even f ly into smallpieces spontaneously.

l'n annealing glassware commerically, it is customary to pass the ware,disposed in several longitudinal rows side by side on a metallicconveyor, through a passage or tunnel heated to a low red heat at theentrance end for 20% or 25% of its length and having,r a graduallydecreasing temperature toward the discharge end where it approachesatmospheric temperature. Such an apparatus is known as a tunnel lehr. Inthe usual practice of annealing with such tunnellehrs` the first step isan attempt at ualizingr the temperature in each article y re heating itto approximately a low red heat, or at least to a condition suliicientlyplastlc to release any stresses existing therein. After this the articleis gradually cooled as it asses through the tunnel.

n the construction of the usual lehrs Serial No. 19,615.

above described, the ware is carried through the tunnel on a conveyor,which may be composed of a series of slats or pans carried by chains.Whatever the construction of this conveyor, it is of necessity spacedfrom the floor ofthe tunnel, and the space between the conveyor and thefloor forms, in effect, a flue through which air currents pass in onedirection or the other and in which convection currents are continuallyin. circulation. No attempt has been madeV to control or regulate theair currents setup in the lehr below the conveyqrand above the tloor,and as the lehrs are usually horizontal, the longitudinal flow of airthrough this flue, formed below the conveyor, has been subject toconstant variations during;r the operation of the lehr, depending uponoutside circumstances, such as the direction of the wind.

The horizontal position of the lehr has caused the same result in theair currents in the space above the conveyor, that is, at one time theremay be an out-draft al the receiving end of the lehr and at another timethere may he an indraft. making a uniform treatment of the wareimpossible. Thus, it is apparent that the structures heretofore employedhave of necessity produced uncontrollable air currents at uncontrolledtemperatures, which prevented uniformity in the continued operation ofthe lehr, and made it impossible to subject the articles in a singletransverse row across the conveyor to the same heat conditions.

Such lehrs require a large amount of fuel. Moreover` the annealing doneby them is frequently more or less uncertain and incomplete, due notonly to inadequate control of the initial heating and the rate ofsubsequent cooling of the ware, but also to considerable differences intemperature between different points in the same transverse section orzone of the tunnel. This causes or permits too wide a difference intemperature between different ortions of the same article and betweendlerent articles of the same transverse row as the articles advancethrough the lehr. Under these conditions, an extremely slow rate ofcooling is employed in an attempt to anneal the particular articlesunder the most adverse heat conditions, Even with this slow rate ofcooling these conditions tend toward faulty annealing of Various methodsand apparatus havebeen provided for the purpose of maintaining all partsof each article and all of the ware in each transverse row in the lehr,at ap-V proximately the same temperature While cooling. If there is anysubstantial difference in temperature indifferent parts of the samearticle, itwill not be properly annealed and if one article in atransverse row varies greatly in temperature from another article, oneor the other of the articles will not be properly annealed unless thetemperature changes are made at such a slow rate as to accommodate thearticle at the abnormal temperature.

If all portions of a glass article, which is being annealed, are broughtto a uniform annealing temperature, and are held at this temperature asutlcient time to permit the release of strains, and if the subsequentcooling be kept uniform as to all portions of the article, it can becooled and annealed perfectly, which result is not possible in the usualcommercial lehr. This is an ideal condition for annealing and permitsthe article to be annealed and cooled in a minimum time, as forinstance, with certain kinds of Ware, in less than one hour as cornparedWith two andone-.half to five hours 1n the l. old-style lehr The nearersuch ideal conditions can be approached in a tunnel lehr, the moreetlicient and better` will be its annealing.

A more complete discussion of the abovementioned factors will be foundin my copending application for Letters Patent, Serial No. 661,827,filed Sept. 1o, 1923, on many features of which the present applicationconstitutes an improvement.

The general objects of the present invention are to produce betterannealing of glassware, to save as much fuel as possible in theannealing, and to reduce the time of annealing, as well as to overcomeor minimize various disadvantages of existing tunnel lehrs.

More specifically, the object is to create a proper environment throughwhich the glassware may be moved continuously on a conveyor an'd inwhich it may be subjected, as nearly as possible, 'to the ideal coolingconditions to produce the best possible annealing and to reduce the timeand cost of the operation.

Another object is to provide improved means and methods for controllingthe temperature throughout the length of a lehr tunnel so as to produceas near the ideal environment for the ware as possible.

Another object of the invention is to overcome the uncontrolled aircurrents which. as previously mentioned, have heretofore existed bothabove and below the conveyor. This object is accom lisled by arrangingthe lehr at a slight inclination which induces a draft of l`air towardthe higher, hot end, thus preventing any air currents from flowing inthe opposite direction and securing control -of such convection currentsas may exist. In order to prevent air currents from owing belovvr theconveyor the present lehr provides a conveyor in 'direct contact withthe lehr Hoor on one side and the Ware on the other.

Another object is to control the local convection currents within thetunnel and utilize them in producing the desired thermal environment forthe ware and in producing as nearly a uniform temperature as possiblethroughout any article or transverse row of articles.

Another object is to provide a lehr tunnel composed of standard sectionswhich may be placed end to end to any desired length. More specificobjects are to provide various structural features to be pointed outbelow.

In carrying out the foregoing objects` I provide a lehr having aplurality of lower fines extending longitudinally beneath the tunnel anda plurality of upper ilues extending longitudinally above the tunnel,all of said Hues being provided with dampercontrolled openings arran edat spaced intervals throughout their length and communicating with theoutside atmosphere.

Heated gases are passed through the lovvert .dues from the receivingyend of the lehr toward the delivery end thereof, and the temperature ofthe gases, and therefore the temperature of the floor of the tunnelthroughout its len h, is controlled at will by adjusting the ampers inthese flues to dilllute the gases with air at selected interv s.

Cooling air is passed through the u )per tlues in a direction oppositeto that o the flow of the heated gases, and the cooling effect of theair is also regulated to control the temperature of the top of thetunnel throughout its length by adjusting the dempers in these tlues topermit more or lessof the air .to escape to the outside atmosphere atselected intervals.

By properly adjusting the dampers in both the upper and lower-fines, thetemperatures atthe bottom and at the top of the tunnel may beindependently regulated so as to control the circulation of localheatconvection currents in the tunnel thereby rendering it possible todistribute the heat uniformly both vertically and transversel)v of thetunnel. ""v

Ware is carried through the tunnel by an endless conveyor, preferablycomposed of dexible Woven Wire fabric, the ware-bearing strand of whichrests directly upon the Hat floor of the tunnel. By reason ofethe lightweight and open construction of the conveyor, it has low heat capacityand relatively great surface area in proportion to its mass, andtherefore follows very closely the tem erature of its environment.

T e roof or upper wall of the tunnel is constructed of metallic sheetsprovided with a plurality of parallel, longitudinally-extendingcorrugations substantially V-shapc in cross-section. These corrugationsprovide the coolinr lues, mentioned above, for conducting coo ing airadjacent to the top of the tunnel, and they also provide a top ofrelatively great heat-radiating surface in com iarison with the width ofthe tunnel.

The angularity of the sides of the corrugations is such as to dispersetransversely the radiated heat reflected from their surfaces and also toproduce a transversely distributed effect in absorbing radiated heat. Inthis way they tend to produce a uniform distribution of heat throughoutany transverse zone of the tunnel.

These features, as Well as additional features of novelty to behereinafter pointed out, will be best understood from the followingdesci'iption, together with the accompanying drawings, in which:

Figure 1 is a diagrammatic side View of a lelii constructed inaccordance with my invention;

F ig. 2 is a vertical longitudinal section through the receiving end ofthe tunnel and the tire box, taken on line 2 2 of Fig. 6;

Fig. 3 is a similar view through a succeeding section of the lehr;

Fig. 4 is a View partly in side elevation and partly in vertical sectionof the exit end of the lehr;

Fig. 5 is a horizontal step section through the entrance end of thetunnel and the fire box;

Fig. 6 is a vertical transverse section taken on line 6 6 of Fig. 2;

Fig. 7" is a similar View through the delivery end of the lehr;

Fig. 8 is a fragmentary plan view of the receiving end of the lehr,illustrating the ware-spacing device"for the conveyor;

Fig. 9 is a side elevation of the conveyor 'driving mechanism Fig. 10 isa vertical longitudinal Section thiiugh the mechanism shown in Fig. 9;an Y Fig. 11 is a vertical transverse section through one of thesupports for the top of the lehr, showing the expansion oint between themetallic plates which orm the roof of the tunnel.

The present lehr comprises in general, as

indicated in Fig. 1, an entrance or receiving section A; an exit ordelivery section B; a plurality of intermediate sections C, of andesired number; a fire box D, located beneath the receiving section A; adelivery table or platform E located at the exit end of the tunnel; anendless belt conveyor F the Ware-bearing strand of which traverses thetunnel and the table E, and the idle strand of which returns to thereceiving or hot en'd of the tunnel beneath the lehr; and aconveyor-driving mechanism G.

The several sections of the lelir are supported in end-toend relation toform a tunnel,` by suitable frame-Work 1, which may be adjustedvertically, as by the bolt-andslot construction l shown in Fig. 3. Thetunnel is slightly inclined downwardly from the hot or receiving end tothe cool or delivery eiid to cause a tendency for air to flow throughthe tunnel, in an opposite direction to the ware movement that is barelysutlicient to prevent an inllow of cold air at the hot end of the tunnelwithout necessarily exerting a material cooling influence upon the Ware.Such a cooling infiuence b v a longitudinal current of air may beemployed to a slight extent, if desired, provided the longitudinalcurrent is sutliciently broken up by local transverse convectioncurrents to prevent an injurious effect from stratification of air atdifferent temperatures. In this Way, the local convection currentsmoving transverse to the longitudinal current will permit the coolingeffect of the longitudinal current and lstill tend to produce a uniformtemperature throughout any transverse Zone of the tunnel. The bottomwall of the receiving section A, and several of the succeedingintermediate sections C, may be constructed as shown in Figs. 2 and 3,of heat insulating brick 2 laid on a bed of heat-insulating cement Thecement bed 3 is, in turn, supported bv a bed plate 4 and side channelbars 5 (Fig. 6) which latter constitute a part of the frame-Work 1.

The side walls of the sections A and C of the lehr each comprise spacedinner and outer parallel sheet metal plates 6 and 7, respectively (Fig.6) which provide a hous-` ing for insulating material 8, such aspowdered kieselguhr or mineral wool. Outer plates 7 at each side of thelehr are rigidl secured together, but the inner plates 6, which aresubject to the heat of the tunnel, 'overlap each other for slidingmovement to permit their longitudinal .expansion without buckling, andmay be provided with bright heat-reflecting inner surfaces. The thinsheet-inetal plates 6 may be quickly heated up to their workingtemperature with a minimum amount of heat, since their heat capacity'isvery low. The insulation Soutsi e of these plates reduces thedissipation of heat to the outside, so that only a Lminimum amount ofheat is required to maintain the lehr tunnel at the desired temperature.The bright inner surfaces of the plates 6 reflect the heat radiated fromthe ware and together with the outer plates 10, form a vide two parallellongitudinal heating lurality of longitudinal and parallel coollng iues13, whlch project into the tunnel space, as best shown in Figs. 6 and 7.The upper bends or corrugations of the lates 9 may, if desired, beslightly spaced elow the upper plates 10, so as to permit an exchange ofair between the several cooling dues, which tends to equalize thepressure and temperature therein. In addition, the corrugatlons providea root` for the tunnel having a relatively large heat-absorbing Surfacein comparison to the width of the tun nel. The angularity of the sidesof the corrugations 12 is such as to reliect the radiated heatdownwardly at an angle to the vertical and to absorb heat radiated frompoints to o'ne side of the vertical, thereby tending to equalize thetemperature transversely of the tunnel. The beams 11 are formed with aseries of V-shaped depressions to accommodate the corrugations 12 andprovide seats therefor. The upper surfaces of the beams 11 are alsoformed, as best shown in Fig. 11, with parallel channels 14 adapted tocontain an insulating packing 15 upon which the edges of the plates 9and 10 are secured for a limited degree of sliding movement by metallicstrips 16 and bolts 17 threaded into the beams 11. Sufficient clearanceis provided between the opposed edges of the plates 9 and 10 to permittheir longitudinal expansion when heated.

The top of the lehr above the heated end and above several of thesucceeding sections is insulated, to retard the cooling of the Ware, byseveral layers of fibrous insulatingr material in the form of superposedslabs 18, the number of layers of which is reduced toward the cold endofV the lehr. The side walls and top of the delivery section B of thelehr are not insulated, as at this point it is desired to accelerate thedissipation of heat from the ware as much as is possible. I

Within' the lehr and sup orted by the refractory bottom 2 are a purality of in verted Achannel members 19, which are preferablyconstructed of cast iron, and are arranged in end-to-end relation inpairs longitudinally of the tunnel. These members form the floor of thetunnel and ro' ues 20. The channel members 19 are maintained againstdisplacement by cli s 21 which engage lips 22 formed in the sides of themembers, and by bolts 23 (Figs. 3 and 5) which extend through bosses 24provided near the central portion of one end of each of the members 19.The bosses 24 also act as additional supports for the bottom of thetunnel and assist in preventing the working thereof.

For the purpose of rovidin expansion joints between the mem ers 19, t etop edge wof the fixed end of each of these members overlaps a channel25 (Fig. 2) which is formed in the adjacent edge of the next`succeeding' member and which is {ille-d with a gas-tight packing 26.Sufficient clearance is allowed between the opposed edges of the members19 to permit their longitudinal expansion when heated. Since the members19 are anchored to the bottom of the Vlehr at one of their ends only,they are free to ex and toward the opposite end without warping orbuckling.

The lehr is heated by a burner 27 (Fig. 2) which projects a flameforwardly through an opening 28 into a combustion chamber 29 provided inthe lire box D. Thisvcbamber is provided with an inner liningl 30 ofrefractory material and with an outer covering 31 of heat-insulatingbrick supported by transverse channel bars 32 secured to the frame 1 ofthe lehr. 2

The character of the combustion in the chamber 29 may be observedthrough two ports 33 disposed one on eaclgl side of the burner inlet 28,as best shownin Fig. 5. As the products of combustion from the burnerpass forwardly. they enter a relatively wide portion 34 of the chamber29, where thev are diluted. to lower their temperature. by air from theoutside atmosphere which is admitted through two parale lol ducts 35provided in the bottom of the chamber. Observation ports 36 are alsoprovided in the side walls of the chamber 34. The amount of diluting airthat is admitted to the chamber 34 through the ducts 35 is regulated atwill by dampers 37 which may be manipulated. if necessary, to admit moreor less air to one side or to the other of the chamber, thusdistributing the heat equally transversely of the chamber.

As the products of combustion pass forwardly they encounter a bale 38(Figs. 2 and 5) provided on the bottom of the chamber 34. over whichthey pass through spaced' ed transversely of the lehr as they emergefrom the ports 4 by reason of their tortuous passage from the combustionchamber 29. The heated gases in this condition then rise through spacedvertical fines 42and encounter an angle plate 43 which forms acontinuation of the metallic bottom of the tunnel and which deflects theheated gases rearwardly into the heating tlues 20, beneath the lehrtunnel. The construction of the fire box D and its arrangement beneathAthe receiving end of the lehr not only insures that the products ofcombustion are thoroughly mixed before they are admitted to the heatingilue 20, but reduces the size of the lehr, and permits easy access tothe entrance 0f the tunnel and to the conveyor.

The heated gases are drawn throu li the lues :20 by a motor-drivenexhaust an 44 shown in Figs. 1 and 4, which is mounted on an overheadframe Astructure 45. This fan communicates, through a pipe 46, with apair of vertical flues 47, disposed one on each side of the lehr andcommunicatin at their lower ends, through a transverse uct 48, with bothof the lues 20.

The temperatures in the flues 20 are regulated by the admission ofregulated amounts of air from the outer atmosphere at suitably spacedpoints lengthwise of these lues. Such admission of air is controlled bmeans of dampers 49 provided at openings 50 which are located atintervals along the tlues 20 and which communicate with the outsideatmosphere. One of these openings, with its damper arrangement, is shown`in Fig. 3, and others are indicated in Fig. 1. A damper 51 is alsoprovided in the pi e 46 to regulate the draft produced by tlie fan 44.

Cooling air is forced through the ilues 13 in the top of the lehrtunnel, in a direction opposite to that of the flow of the heating gasesin the l'lues 20, by means of a fan 52 shown in Figs. 1 and 4. This fanis mounted on the blower-sup orting frame 45 and communicates with all)pf the lues 13 through a common flue or conduit 53 provided with adamper 54.

, The temperature adientor curve in the portions of the cooling fines 13adjacent to the cooling zone of the tunnel, that is to say, the rate auddegree of variati-ons` iu temperature longitudinally of these fines, maybe alsorcgulated by dampers 55 rovided in spaced stacks 56 (Figs. 1:ind2 3) which communicate `with the outside atmosphere through the topof the lehr.

By ropeily adjusting both the dempers 49 and) 55 in the heatinfrflues 2Q`and the cooling flue 13 respectively, the desiredteinperat-uregradients may beobtained in these fines and the portions ofthe ltunnel'adjacent thereto. That is to sa ,uthe character 0f thetemperature curves o tained by plat- Athe same time that he isregulating'and observting temperatures as ordinates against distancealong the lehr as absciss, in both the heating flue and in the coolingflue is determined by the number of the damper-controlled openings, b'the amount that the dampcrs are opene to the outside atmosphere, andalso by the location of the dampers. For example, the less the amount ofcooling air from the outer atmos here that is permitted to enter the`forwar or hotter gortions of the heating lues 20, the greater t istancewill the heat in these flues influence the temperatures therein; and theless the amount of cooling air that is allowed to escape from the rearor cooler ends of the cooling flues 13, the greater distance will thecooling air traverse these flues. It therefore follows that byregulating the amount that the gases in the eating {lues are diluted andcooled by outside air, and by regulating the amount of cooling airescaping to the atmosphere from the cooling lues 13 and'by alsodeterminin the location of the dampers that are adJusted, the resultanttemperature tgradients of the top and bottom portions o the tunnel maynot only be controlled at will, but the point or zone of maximum drop inthe temperature curves may be shifted longitudinally of the tunnel. p

By thus heatingv the floor of the tunnel to cause upwardly movingconvection currents and by cooling the top of the tunnel to causedownwardly moving convection currents and by independently regulatingthe degree of heatin and cooling, the rate of movement of the convectioncurrents in the tunnel maybe controlled at will, thereby rendering 1'tpossible to obtain a substantially uniform temperature, so far as itseil'eet upon the ware is concerned, in a vertical direction in anytransverse section or zone in the tunnel. v

The draft in the combustion chamber may be controlled independently ofthe dam er 51 by a dam er 57 which, as shown in 11g. 3, is provide in atransverse U-shapedwluct- 58 which is formed in the bottom et the lehrand which establishes communication between the parallel heating flues20. This damper, for convenience, is operated by means of n suitableserew-threaded rod provided with a lian'd wheel 59 (F ig. l) that is loated at a point adjacent to the [ire box Dttpspermitting the operator toregulate aft in the combustion chamber at the lng the character of theflame delivered by the burner.

The receiving table E consists of a plurality of spaced parallellongitudinal bars or rails G0 Figs. 1, 4 andAlO) which are supported attheir forward ends by the frame of the deliverv section B of the lehr`and at their rear ends by a frame 61 of the ioo beit driving mhmim G.This 4time p vides a support 'for the conveyor as it together with einerfrom the tunnel bear" the anneale ware, and is of suicient ength topermit severaliersons to standside by side on each side o the table toinspect and remove the ware from the conveyor for ack- The conveyor Fand the table are :u ciently narrow to it easy access. from either sideof the table, to ware located in the central portion of the conve or.

The conveyor F is an endle belt of exible o structure, the ware-bearingstrand of which lies dat vupon the cast iron inverted channel members19,v which constitute the bottom of the lehr tunnel. and u n .the railsof the receiving table E. prefer that the conveyor belt be composed ofwoven bo wire fabric, as the relatively small amount of metal employedin a conveyor of such its openwork structure, insures a low heatlcapacity, a large heatradiating suracearea in comparison with its mas,maximum radiation of heat through the openinthe conveyor, and minimumcontact with both the bottom of the tunnel and with the'ware. 4

As best shown in Figs. 9 and 10, the con veyor. as it advances over theend of the receiving table E, passes over a roller 6'2 journaled in theframe 61 and thence forwardly and around a4 drivin drum 63 which i n anidler roller 83`and is mounted on a shaft 64 Journaled in the frame 61.vAt the point where the beltA leaves the drum 63 it passes-over andrearwardly around a roller 65 which is journaled at its ends in sideblocks 66, mounted in ways 67. The drum 63 and the roller 65 areprovided with resilient anti-slippin coverings 68 and 69 respectively,compose of rubber or the like, so as to' present a tractive surface, tothe belt and insure a ositire driving contact-therewith. The ro er 65 ismaintained in 4grip ing contact with the belt F by jackscrews lit) whichare threaded Vin the waysl 64 and '6T and which bear against the sideblocks 66. Y

The drum 63 and the roller 65 are rotated by a. sprocket wheel 71, whichis driven in any preferred manner. The s rocket wheel 71 is mounted onashaft 72 w ich carries a worm`,73 mesh? with a worin wheel 74 carried bya sha 75. A inion 76 is also keyed to the shaft 75, an

gear wheel 77 mounted on a shaft 78. A

' pinion 79 is also keyed ,to the shaft 'I8 and meshes with a gear wheel80 carried by the drum 63. The gear wheel 80 meshes with a ar wheel 81on the roller 65`whereby both edmm and roller are driven at the sameperi heral speed.

Tge conveyor belt F, after around the roller 65-passes forward ly anaround upwardly and .lehr tunnel into meshes with a over a roller 84carried. by the frame 61. The idler roller 88 isv carried by arms 85which are pivotally connected to a shaft 86 carried by the frame-Blandmay be augusted to take u any slack in the belt by means of adlustablerods 87, which are secured at their rear ends to the arms 85, and attheir forward ends to the frame 1 ofthe delivery section B of the lehr.After leaving the roller 84, the. belt F wardly beneath the lehr and issupported at intervals by rollers 88 which are mounted passes forv onthe frames 1 of the several .sections of v supported, as shown-AinFig.2, by a guidetrack 89 disposed beneath the fire Y* As the belt leavesthis track, it passes around a. roller 90 and u wardly parallel to thefront end of the fine ox and way or thence over a roller 93 disposed a 4'acent to the entrance of the tunnel. From e roller` 93 the belt passesover the an le plate `43 and into the front end of theehr tunnel. Inorder to faclitatethe ton of heat from the anglelate 43 'to the conveor, this element is pre ably rovided witlia ribbed upper surface'94 ig.5), mg a be the case if the baille 43 resented a at surface to theconveyor be t. The ribbed surface also reenforces the baille and tendsto prevent any warping Vof this element through expansion andcontraction`.`

The-upper portion of tlieentranee of the tunnel is closed by ablock orslab 95 of insulating material, the lower edge 'of which terminatesat asuicient distance from the conveyor to permitthe .passa of waretherebeneath. An insulating bFe ned' hva forwardly and rearwardlyadjust` able 2- late 96* is mounted on the bottom of the le at` a slightdistance from the timnel o ing and maycari'ya plurality ofspaeemi'ertical wire mesh partitions 9 7. These partitions separate thewidth: of the equal spaces, each of sollicient width to accommodate ,abottle, thus insurin that the ware is verse y of the tunnel en placed.on the conveyorbelt by the carrying-in boy in in stallations notequipped with a mechanical lehr-stacking device.

The blocks 95 and 96 together practically close the entrance end of thetunnel in a horizontal direction and tend to retard the flow' of airthrough the tunnel. Bv reason of theotl'set dis thus givbetween them ina vertical direction in de-.. ositing it on the conveyor. block 4320iAlieat insulating material is disposed ad1a` greater heat-radiating areathan would l ock 96 car-` r ially spaced translll l ition of thesebloclxs relal tive to each ot er, 'ware mav be inserted` cent to themember 43 andpreventa air from" entering the tunnel beneath the blpk thetunnel at 'any desire Sufficient space is, however, provided between theblocks. 43 and 96 to permit the conveyor to pass therebetween.

The Ware is prevented from contacting with the inner side Walls 6 of thetunnel by means of longitudinal ribs 98, which are secured to the side,Walls of the tunnel adjacent to the surface of the conveyor belt.

Pyrometer elements ma be inserted into points for indicatin thetemperatures within the tunnel. For t iis purpose, pipe sections 99 areshown on Figs. and extending through the top of the lehr and held inplace by nuts 100. Similar inlet pipes for inserting pyrometer elementsmay be provided in the side walls4 as shown at 101, Fig. 7, for thepurpose of determining the temperature in the heating lues.'

In operation, the ware is deposited on the conveyor F and is carried bythe conveyor into the tunnel. During the first part of its travelthrough the tunnel, the ware is subjected to a temperature necessary tobring it to a uniform temperature and to hold it at this temperature fora snlicient time to permit of the release of strains. After the strainshave been relieved the Ware is carried by the conve or into anenvironment of a gradually ecreasing temperature through which Vitpasses until it emerges from the tunnel at the delivery end thereof theglass is set by this time, it ma be, 1n some cases, still too hot to behand e and it is therefore carried for a short distance along the tableE where it is subjected to the coolinor etl'ect of the outsideatmosphere and rapid .y loses its heat.v The openwork structure of theconveyor and the table E, permits heat to dissi ate from the Ware, inall directions', by ra iation and convection. As soon as the Warereaches a temperature where it can be comfortably handled, it is removedfrom the conveyor, inspected and packed b operators stationed on eachside of the ta le E. After passing,over the end of the table E, theconveyor passes throu h the drivin mechanism 4 G heretofore escribed anthence forwardly beneath the tunnel to its entrance end.

By properly adjusting the various dampers 1n the Vup er and lower fines,the temperature of t e tunnel may be regulated to suit the particularrequirements of the e of Ware being annealed. or exam le, if the initialheat contentof the ware at t ie time that it is delivered to the lehr isinsutlicient, after having become -uniformly ldistributed throughout theware, to permit the strains existin in the glass to be effectivelyrelieved, additional heat must be supplied to the ware from an externalsource. In such cases the temperature in the fines 20 in an annealedcondition. Although is maintained suiiiciently high, through a portionof their length, to maintain the environment of the tunnel for acorresponding distance at a temperature at which strains in the Glassmay relax within a reasonable time. 'he flues 2O throunfhont thisparticular portion oftheir length function as heating flues.

After the Ware reaches this temperature, the cooling operation may bebegun, and the rate at which the ware is cooled from this Vpoint on isdetermined byV proper adjustment of the various dempers. It may occurthat, owing to thcrparticular character of the ware, the coolinoperation may be accelerated and in suc instances the ilues 20 mav beutilized throughout the remainder of their length as cooling lues badjusting the dempers 49 so as to lower t etemperature in these finesbelow that of the ware.

In other cases suiicient initial heat is retained in certain portions ofthe ware, so that after it has become uniformly distributed throughoutthe ware, the temperature thereof is suiciently high to permit thestrains to be relieved. Under such condi tions, it is unnecessary tosupply additional heat to the ware and the temperature in the iiues 2()ma consequently be maintained lower than that of the ware, and thesetiues may thus function as cooling flues throughout their entire length.In such instances, the temperature in the flues 20, while being lowerthan that of the Ware, is maintained sufciently high to restrict thedissipation of heat therefrom to the proper rate.

The dempers 49 in the lues 20 permit a very flexible control of thetemperature in these fines, as the bottom of the tunnel, being ofmetalli;- construction, follows very closely the temperature in theselues. It, therefore, follows that b v properly manipulating the dampers49 in the lines 20, the exchange if heat between the Ware and themetallic bottom of the tunnel may be also verv accurately controlled.

y means of the above-described features, such as the tunnel Wallconstruction, which provide for roper insulation. radiation andreflection of lient; the corrugated top or wall, adapted to uniformtransverse thermal effects: andthe fines above and below the tunnelseparatedtherefrom by their metal walls, which control the rate ofmovement of convection currents; the temperature of the ware throughoutany transverse section or zone of the tunnel is made so nearly uniformas to approximate the ideal environment. The temperature in anytransverse Zone of the tunnel is substantially the same, so far as itseffect upon the ware is concerned, in the top, bottom, sides and cornersof that zone.

Thus, as the articlespass through the Successive zonesof the tunnel,they retain or Yacquire the progressively falling temperatures of thosezones, and all portions of every article A through any-zone acquireapxiniately the temperature of that zone with suilicient uniformity forpractical annealing. By this a paratus and method of temperature controaverage glass articles may be annealed in a verv short time, re-

uiriiig in many cases less than one hour for t e annealing-and finalcooling. as against the usual time. of two and one half to five hoursrequired by the best previous commarcial annealin lehrs.

The various tur@ of the invention herein described` as incorporated in asingle organized apparatus may be used separately` or inpothercombinations, and various modifications may be made in the arrangementand construction of the parts, and in the method of cooling the articleto be annealed. For some uses, as for example for the haiidling of onlyone kind of ware, some of the adjustments and other provisions forhandling varied kinds of ware may be dispensed with. The lehr tunnel maybe made integral throughout its length. In this and in other ways themethod and apparatus herein described and shown may be modified withinthe scope of the appended claims.

I claim 1. The method of annealing glaware, which comprises passi aseries o glass articles throu h a tunne heating a wall of saidtunnelrliy passing a current of heated gases adjacent thereto, andregulating the heating of said wall by cooling said gases atpredetermined intervals in the path of travel thereof.

2. The method of annealing glassware, which comprises passing a seriesof glass articles through a tunnel, heating the bottom of said tunnel byassing a. current of heated gases therebenea and regulating the heatingof said bottom by coo ing said gases at predetermined intervalslongitudinally of said tunnel. a a

3. The method of annealing glass ware, which comprises passin a seriesof glass articles througlli a tunne heating a wall of said tunnel ypassing a current of heated gases adjacent thereto, and regulating theheating of said wall by diluting said gases with cold air from the outeratmosphere at predetermined intervals in the path of said gases.

4. The method of annealing glass ware. which comprises passing the warethrouth a tunnel, heating the lower portion of e tunnel to causeupwardly moving convection currents, cooling the u r portion of thetunnel to cause downwarl)e moving conyection currents, and inde gentlyregulating both the heating and ncoolin o said portions of the tunnel atintervalsongitudinally thereof to control the reteof movement of saidconvection currents.

A 5: The method of annealing glassware, which comprises passing the warethrough a tunnel. heating the lower portion of said tunnel to causeupwardly moving convection currents. cooling the up r portion of thetunnel to cause downward y moving convec tion currents, and inde ndentlyregulating both the lieatingan the coo 0f said portions of the tunnel atinterv in the path of travel of the ware to selectively retard andaccelerate the movement of said convection currents to obtain asubstantially uniform temperature in said portions of the tunnel and tovary at will the temperature gradient in said tunnel.

6. The method of annealing aware, which comprises paing ware ugh atunnel, directing a current f heated gases adjacent to the tunnel! anddiluting said current at intervals with atmospheric air to lower thetemperature of said tunnel below that of the ware and to control at willthe tem rature gradient in said tunnel.

7. A. ehr for glaware comprising a-tunnel, a liuc asociated with saidtunnel, means for causing a heating medium to flow through said flue,and means for reducing the temperature in said flue selectively at anone of a plurality of intervals along said ue, and for thereby changingat will the temperature within said tunnel.

8. A lehr for annealing glassware oomprising a tunnel, a flue associatedwith said tunnel, means for c using a heating medium to llow throughsaiV flue, the said flue being divided into a plurality of independentlycontrollable heating zones, and means for increasing or decreasing atwill the temperature in any of the said zones.

9. A lehi` foi' glassware comprising an annealing tunnel, a heated'iluedisposed beneath said tunnel, a cool flue dis osed above said tunnel,and means for in ependentl regulating the temperature gradient in eac ofsaid lines longitudinall of the tunnel to vary the temperature gra ientin said tunnel.

10. A lehr for glassware comprising an annealing tunnel, a heating flueand a cooling ilue associated with said tunnel, damper controlledopeningsin said flues communieating with the outside atmosphere forindependently regulating the temperature gradient in each of said iluesto vary the temperature gradient in said tunnel.

11. A lehr for glassware comprising a tunnel, a line associated withsaid tunnel, means for causing heated to llow thro ugh said flue, andmeans for dilutinn the in said line with air to vary at the tem uregradient in said tunnel.

12. l for lasswareoom "atunnel, alue exteiiug longitueeth of saidtunnel, and

tervals to vary at will p produced in said said tunnel, means forcausing hot gases to How through said Hue, and means for introducingatmospheric air into said Hue at inthe temperature gradient in -saidtunnel.- v

13. A lehr for glassware com rising a tunnel, a Hue extendinglongitudinally beneath said tunnel, means for causin heated gases to Howthrough said Hue, an means or diluting said gases with air from theoutside atmosphere at intervals in the of travel of said gases toregulate the temperature drop in said Hue and tunnel.

14. A Ylehr for glassware comprising a tunnel, a Hue extendinglongitudinally beneath said tunnel, means for causing heated gases toHow through said Hue, and a plurality of damper-controlled openingsarranged at intervals longitudinally of said Hue, and capable of beingselectively opened to admit air into said Hue to vary at will thetemperature gradient in said Hue and tunnel.

15. A lehr 'for glassware comprising a tunnel, a Hue extendinglongitudinally beneath said tunnel, means for causin heated ses t0 Howthrough said Hue to eat the ower portion of said tunnel, a Hue extendinglongitudinally above said tunnel, means for causing cooling air to Howthrough said last-mentioned Hue to cool the upper portion a plurality ofdampercontrolled openings arranged at intervals longitudinally of bothof said Hues and coinmunicating with the outside atmos here to va atwill the temperature gra ient in sai tunnel.

16. A lehr com rising a tunnel, said tunnel being inclinedpdownwrdlyfrom its receiving end to its delivery end to cause a tendency for theheated air therein to accumulate adjacent to the entrance thereof, a Hueextending longitudinally beneath said tunnel, means for causing a How ofheated gases through said Hue, and means for admitting regulablequantities of air from the outer atmosphere into said Hue at intervalslongitudinally thereof to dilate the gases in said Hueand vary at willJthe temperature gradient in said tunnel.

17. A ehr comprising an annealin tunnel, a heating Hue extending longituinally benath said tunnel, a fire box located bebeneath said tunnel, afire box located bemeans for causing products of combustion fire box toHow vtoward the receiving endof said tunnel, and then in the op ositedirection through said flue.

18. lehr comprising an annealin tunnel, a heating Hue extendinlongitucnally beneath said tunnel, a lire gbox located beneath thereceiving end of said tunnel, means for causing roducts of combustionproduced in said fire ox to How toward the receiving end of said tunneland then in the opposite direction through said Hue, and means for pathcombustion chamber controlling the How of said products of combustion.

19. A lehr comprising an annealin tunnel, a heatingHue extendin lon ituinally beneath said tunnel, a fire ox ocated beneath the receivin end ofsaid tunnel, means for causing prodgucts of combustion produced in saidfire box to How toward the receiving end of said tunnel and then in theopposite direction through said Hue, and means for causing the saidproducts of combustion to traverse a tortuous path while passin fromVsaid fire box to said Hue.

20. lehr comprising an annealing tunnel, a heating Hue extending lonitudinally beneath said tunnel, a fire box ocated beneath the receivingend of said tunnel, a in said fire box, means for causing products ofcombustion produced in said combustion chamber to How toward thereceiving end of said tunnel and then in the opposite direction throughsaid Hue and a plurality of baille elements in the path of travel ofsaid products of combustion to cause a tortuous How of said prodcts inpassing from said chamber to said 21. A 'lehr comprising an annealintunnel, a heating Hue extending lon itu inally beneath said tunnel, afire box lgocated beneath the receiving end of said tunnel, a combustionchamber in said fire box, means for causing products of combustionproduced in said fire box to How toward the receiving end of said tunneland then in the opposite direction through said Hue, and means forintroducing atmospheric air into said fire box to dilute the saidproducts of combustion and regulate the temperature thereof.

22. A lehr comprising an annealing tunnel, a heating Hue extendinglongitudinally beneath said tunnel, a fire box located beneath thereceiving end of said tunnel, a combustion chamber in said lire box,means for causing the products of combustion roduced in said combustionchamber to ow toward the receiving end of said tunnel and then in theopposite direction through said Hue, and means for regulating the draftin said combustion chamber to uniformly distribute the heat thereintransversely thereof.

23. A lehr comprising an annealing tunnel, a heating Hue extending lon'tudinally beneath said tunnel, a fire box ocatcd beneath the receivingend of said tunnel, a combustion chamber in said fire box, means forcausing roducts of combustion4 produced in said combustion chamber toHow toward the receivin end yof said tunnel and then in the oppositedirection through said Hue, and means for shifting the draft in saidcombustion chamber transversely thereof.

24. A lehr comprising a tunnel, a member for closing the upper portionof the entrance cud of said tunnel, and a member for closing the lowerportion of the entrance end of said tunnel, said members being disposedin different vertical planes to permit ware to be inserted between saidmembers in depositing it in` said tunnel.

Q5. A lehr comprisinor an inclined tunnel a member for closing the upperportion o the upper end of said tunnel, and a member for closing thelower portion of the upper end of said tunnel, said members being ofisetrelative to each other longitudinally of said tunnel and adapted toretard the flow of air through said tunnel and to permit ware to beinserted vertically between said members in depositing it in saidtunnel.

26. A lehr comprising an inclined tunnel, means for retarding the ow ofair through the entrance of said tunnel, said means including a baiilemember closing the up er portion of the entrance and a bailiemem erclosing the lower portion of the entrance, said baille members beingotlset with respect to each other to permit Ware to be insertedtherebetween indepositing it in said tunnel.

27. A lehr comprising a'tunnei, a member for closing the upper portionof the entrance end of said tunnel, and a member for closing the lowerportion of the entrance end of said tunnel, said members being oil'- setwith respect to each other to permit ware to be inserted between saidmembers in depositing it in said tunnel.

28. A lehr comprising a tunnel and a plurality of iues dis osed adjacenta wall thereof, and eac having a portion projecting bodily` into saidtunnel and exposed to the air in the said tunnel.

29. A lehr comprising a tunnel having a plurality of iues disposedadjacent to a wall thereof, and in spaced relation with respect to eachother,to ermit the air in said tunnel to circulate etween said tlues.

30. A lehr comprising a tunnel having a iue depending from the topthereof to expose the sides of said Hue to the air in said tunnel.

31. A lehr comprising a tunnel having a wall including a member providedwith a plurality of corru ations, said corrugations forming a series ofines on one side of said member and a series of heat-reflectingsurfaces on the other side thereof.

32. A lehr comprising a tunnel having a wall thereof formed of aplurality of sheet metal members provided with a plurality ofcorrugations, said corrugations forming a series of liues on one side ofsaid members and a series of heat-retiecting surfaces on the other ,sidethereof.

33. A lehr comprising a Atunnel having a wall thereof formed of aplurality of sheet metal members, each rovidediwith a plurality oflongitudine y extending corrugametal members arranged in end-to-endrelation longitudinally of the tunnel, each of said members beingrovided with a plurality of longitudinal y extending corrugations, saidcorrugations forming a series of fines on one side of said member and aseries of heat reflecting surfaces disposed at an angle to each other onthe other side thereof.

35. A lehr comprisin a tunnel, a wall of which is constructe of aplurality of sheet metal members, each having a plurality ofcorrugations formed therein, and a sheet metal member arran ed to extendacross said corrugations to bridge the same to form a plurality of lues.

36. A le r comprising a tunnel, the top wall of which consists of aplurality of sheet metal members, each having a plurality ofcorrugations formed therein, a sheet metal member bridging saidcorrugations to form a plurality of spaced lues, and an outside layer ofinsulating material.

37.7A lehr comprising a tunnel the to-p wall of which consists of aplurality of sheet metal members. each having a plurality oflongitudinally extending corrugations formed therein, a sheet metalmember bridging said corrugations to form a plurality of-spaced flues,and an outside layer of insulating material.

38. A lehr comprising a tunnel the top wall of which consists of aplurality of inner sheet metal members, each having a plurality ofcorrugations formed therein, a. sheet metal member bridging saidcorrugations to form a plurality of spaced Iiues, and an outside layerof insulatingr material supported by said bridging member.

39. A lehr comprising a tunnel the top wall of which consists of apluraiity of lin sheet metal members, each having a plui rality ofcorrugations formed therein, a sheet metal member bridging Asaidcorrugations to form a plurality of spaced ues, an outside layer ofinsulating material, and expansion joints provided between said members.

40. A lehr com' rising a tunnel having a bottom constructe of aplurality of metallic l members having a sliding connection with eachother to permit of their independent expansion.

41. A lehr bottom consisting of material and a plurality of metallicmemcomprising a tunnel having a a bed of refractory bers each having oneend secured to said bed to permit said members to expand inl alongitudinal direction.

faov

42. A lehr comprising a tunnel, the bottom of which consists of apluralityof inverted longitudinally extending metallic channel membersarranged in vend-t/o-end relation to provide a flue beneath said tunnel,and means for causing gas to flow through said flue.

43. A lehr comprising a tunnel; the bottom of which consists of aplurality of inverted metallic channel members arranged in end-to-endrelation in pairs longitudinally of said tunnel to provide a pluralityof lues beneath said tunnel, and means for interconnecting said lues toequalize the draft therein.

44. A lehr comprising a tunnel, the bottom of which consists of aplurality of inverted metallic channel members arranged in overlappingrelation with each other longi# tudinally of said tunnel, and means forpermitting independent longitudinal expansion of each if said members.

45. A lehr comprising a tunnel, the bot- A tom of which consists of abed of refractory material, a s lurality of inverted metallic channelmem ers mounted on said bed and arranged in end-to-end relationlongitudinally of said tunnel to pro-vide a flue beneath the same, meansfor securing each of said members to said bed at one end of said member,to permit said member to expand longitudinally in an opposite direction,and a yleldable joint between said members.

46.*A lehr comprising a tunnel having a bottom composed of a pluralityof members arranged in end-toend relation, an edge of each of saidmembers being provided with a flange oii'set relative to the top planeof said members, and adapted to underlie another edge of an adjacentmember, and forming therewith a sliding connection to accommodatemovement of said members in a horizontal direction caused b theexpansion and contraction of said mem ers.

47. A lehr comprising a tunnel having a bottom composed of a pluralityof members arranged in end-to-end relation, an edge of each of saidmembers being provided with a flange olf-set relative to the top planeof said members, and adapted to underlie another edge of an adjacentmember and support a refractory packing, said flange forming a slidingconnection with the edge of said adjacent member, to accommodatemovement 'if said members in a horircontal direction caused by theexpansion and contraction of said members. i

48. A lehr comprising a tunpel havin a bottom composed o f a pluralityof metallic members arranged in end-to-end relation longitudinally ofthe tunnel, an edge of each of said members being provided with ahorizontal Harige offset relative to the top plane of said member andadapted to underlie the edge of the oppositey end of the adjacent memberand support a refractory packing therebetween, said flange and packingforming a sliding joint with the edge of said adjacent member toaccommodate longitudinal movement of said members caused by expansi'onand contraction.

49. A lehr comprising a tunnel having a bottom composed of a pluralityof metallic members arranged in end-to-end relation, an edge of each ofsaid members being provided with a channel adapted to contain arefractory packing, said channel being adapted to underlie an edge ofthe adjacent member and forming therewith a sliding joint to accommodatemovement of said members in a horizontal direction caused by theexpansion and contraction of aid members.

50. A lehr comprising a tunnel having a bottom composed of a pluralityof inverted metallicchannel'members arranged in endto-end relationlongitudinally of the tunnel to form al flue beneath said tunnel, thehorizontal portion of each-of said members bein provided with a channeloffset relative to the plane of said horizontal portion and adapted tocontain a refractory acking and to underlie the opposite end e ge of thehorizontal portion of an adjacent member and forming therewith a.sliding connection between said members to accommodate movement of saidmembers in a longitudinal direction caused by expansion and contraction.i

51. A lehr for annealing glassware comprising a tunnel, a flueassociated with said tunnel, means for causing a heatin to flow throughsaid flue, the said ue being divided into a plurality of independentlycontrollable heating zones, and means, including spaced dampers, forincreasing or decreasing, of the said zones.

Signed at Hartford, Connecticut, this 30th day of March, 1925.

VERGIL ML FHOLLAND.

medium at will, the temperature in any Logins? 4Q. A lehr comprising atunnel, the bottom of which consists of a pluralityvof invertedlongitudinally extending metallic ychannel members arranged inend-to-end relation to provide a liue beneath said tunnel, and means forcausing gas to flow through said flue.

43. A lehr comprising a tunnel; the bottom of which consists of aplurality of inverted metallic channel members arranged in end-to-endrelation in pairs longitudinally of said tunnel to provide a pluralityof fines beneath said tunnel, and means for interconnecting said iiuesto equalize the draft therein. 44. A lehr comprising a tunnel, thebottom of which consists of a plurality of inverted metallic channelmembers arranged in overla ping relation with each other longi-` tudinaly of said tunnel, and means for permitting independent longitudinalexpansion of each` )t said members.

45. A lehr comprising a tunnel, the bottom of which consists of a bed ofrefractory material, a lurality of inverted metallic channel mem ersmounted on said bed and arranged in end-to-end relation longitudinallyof said tunnel to provide a flue beneath the same, means for securingeach of said members to said bed at one end of said member, to permitsaid member to expand lon itudinally in an opposite direction, and ayieldable joint between said members.

46."A lehr comprising a tunnel having a bottom composed of a pluralityof members arranged in end-to-end relation, an edge of each of saidmembers being provided with a flange offset relative to the top plane ofsaid members, and adapted to underlie another edge of an adjacentmember, and forming therewith a sliding connection to accommodatemovement of said members in a horizontal direction caused by theexpansion and contraction of said members.

47. A lehr comprising a tunnel having a bottom composed of a pluralityof members arranged in end-to-end relation, an edge of each of saidmembers being provided with a flange olf-set relative to the top planeof said members, and adapted to underlie another edge of an adjacentmember and support a refractory packing, said flange forming a slidingconnection with the edge of said adjacent member, to accommodatemovement r' "t said members in a horizontal direction certificate ofcori-36am.

It is hereby certified `'that 1926,V u

h in Letters Patent No. l 571 13;? pon the application of VergilMulholland, of,

caused by the expansion and contraction of said members. i

48. A lehr comprising a tunnel havin a bottom composed of a plurality ofmeta lic members arranged in end-to-end relation longitudinally of thetunnel, an edge of each of said members being provided with a horizontalflange oi'set relative to the top plane of said member and adapted tounderlie the edge of the opposite end of the" adjacent member andsupport a refractory packing therebetween, said flange and packingforming a sliding joint with the edge of said adjacent member toaccommodate longitudinal movement of said members caused by expansi'onand contraction.

49. A lehr comprising a tunnel havino a bottom composed of a pluralityof metallic members arranged in end-to-end relation, an edge of each ofsaid members being provided with a channel adapted to contain arefractory packing, said channel being adapted to underlie an edge ofthe adjacent member and forming therewith a sliding joint to accommodatemovement of said members in a hori zontal direction caused by theexpansion and contraction of, said members.

50. A lehr ciimprising a tunnel having a bottom composed of a pluralityof inverted metallic channel'members arranged in endto-end relationlongitudinally of the tunnel to form a flue beneath said tunnel, thehorizontal portion of each'of said members being provided with a channeloffset relative to the plane of said horizontal portion and adapted tocontain a refractory acking and to underlie the opposite end e ge of thehorizontal portion of an adjacent member and forming therewith a slidingconnection between said members to accommodate movement of said membersin a longitudinal direction caused by expansion and contraction.

5l. A lehr for annealing glassware comprising a tunnel, a lue associatedwith said tunnel, means for causing a heatin medium to flow through saidlue, the said ue being divided into a plurality of independentlycontrollable heating zones, and means, including spaced dempers, forincreasing or decreasing, at will, the temperature in any of the saidzones.

Signed at Hartford, Connecticut, this 30th day of March, 1925.

VER-Gl L ML T HOLA ND.

, granted January 26 West Hartford, Connecticut;

for an lmprovement in Methods and Apparatus for Annealing Glassware,errors yappear in the printed s ilication re uir 52, claim 17, fonthemissp'iilled word beCiiat f, -Word and hyphen be; same page and claim``instead beneath iw receiving end of said tunnel, and; and that thethese corrections therein that the same may conform to the ingcorrection as follows: h s

.Page 9, line strike out the 53 and insert said Letters Patread beneath;same line, strike out present line D M. J. MOORE,

Actmg Uowwbzsxz'oner of Pate/nts.

Certificate of Correction.

It is hereby certified 'that in Letters Patent No. 1,571,137, gruntedJanuary 2G, 1926,v upon the application of Vergil Mulholland, of VVe'stHartford, Connecticut, for an improvement in Methods and Apparatus forAnneulinglr Glassware. errors :appear in the printed Specificationrequirin correction as follows: .Page 9, line 52, claim-17, for: themisspelled word benath read beneath; same line, strike out the word andhyphen be; same page and claim` strike out present line 53 and insert4instead beneath the nocivi@ emi of said tun/rml, amd; and that the saidLetters Patent should be read with these corrections therein that thesame may conform to the record 'of the cse in the-Patent Olice.

Signed and sealed this 6th day of April, A. D. 1926.

[5mn] M. J. MOORE,

Acting Gamm/issioner of Polenta.

